Write a note on heat resistant steel
These are steels which are exposed to high temperatures during proportion of equipment. Heat resistance is obtained by adding specific metals in appropriate proportion.
Following metals are used/added in stainless steel in order to make them heat resisting.
Molybdenum: 3.5% addition of this metal improves heat resistance of steel.
Chromium: though this is the component in steel, but it is added more than 12%, it imports high grade heat resistance to steel. Such a steel is called as ‘nichrome’.
For making equipment facing high temperature i.e. gas turbines, retorting, parts of boilers, steam – linings, aero engine valves, etc.